bug fix: the argument of '--sysroot' option should be followed '=' character.
bug fix: add new option '-mandroid' into CFLAGS and same options are applied into LDFLAGS.
refactoring
define and use print format macros for mrb_int

For portability: %ld can't be used to print a 64-bit mrb_int on
WIN(32|64) because long is 32-bit wide.
add a new feature to select the target architecture.
add a new feature to select the target Android platform.
more CFLAGS and LDFLAGS are specified automatically.
Remove a meaningless type cast.
Add comments for paradnoid (a.k.a. mission critical) engineers.
Use int. They are no need to use unsigned/signed long. Think about 16bit architectures.
Copy to *lenp just in case lenp != NULL.
Use mrb_int as possible.
Remove compiler warning
Define type mrb_bool. It is typedef-ed to _Bool on C99, unsigned int on MSVC.
It is safer than applying 1bit bit-fields to signed int.

For forward compatibility, you should substiture only 1 or 0 for the variable typed mrb_bool.
Merge pull request #1005 from mattn/remove_warning

Remove compiler warning
Merge pull request #987 from monaka/pr-clean-up-parse.y-20130312

Clean up parse.y.
remove PARANOID from comments
Merge pull request #993 from monaka/pr-cleanup-symbol.c-20130312

Cleanup symbol.c.
symbol length make size_t from mrb_int; cancel #993 monaka/pr-cleanup-symbol.c-20130312
use size_t for string length C API